I can send you a package of 5 separate files that do both format and use tracks 36...40
Some of them are in BASIC.
Anyway, to format 'illegal' tracks, you have to bypass the 1541 O.S., and to code your own routine. It must be put on 1541' RAM, then executed. This includes a deep knowledge of 1541' O.S. and memory map.
I studied it (a few), then if you need any tip, feel you free to ask me for.
